1. Field of the Invention
The present invention relates to a method of fabricating an Organic Electroluminescence (OEL) panel package, and in particular, an organic electroluminescence panel package having area array poly solder interconnection.
2. Description of the Related Art
OEL devices employ the characteristics of self-illumination of organic functional materials to provide the displaying effect. Based on the differences of molecular weight of the organic functional material, there are two categories of OEL, namely small molecule OLED (SM-OLED), and polymer light-emitting device (PLED).
Organic electroluminescence devices use two electrodes to enclose organic film having light-emitting property. When an appropriate voltage is applied, holes will be injected from the anode and electrons will be injected from the cathode. Due to the externally added electric field, which causes potential difference, carriers within the film will move and produce recombination. A partial of energy released from the recombination of electrons and holes will excite the light-emitting molecule to form a single excited molecule. When the excited molecule releases energy and returns to the steady state, a certain proportion of energy will be released as light. This is the principle of light-emitting of OEL elements. The OEL element possesses self-emitting light, wide angle, high responsive speed, low driving voltage, and full color, and is known as the next generation flat display technology. Presently, the OEL element is at the stage of exploitation and in the future, it will be employed in the next generation color flat display, for example, all sizes of display panel, outdoor display panels, computers and TV screens, etc. However, the development of OEL is rather late as compared to that of the display, and the technology has not fully matured. Thus, there is room for improvement in the commercialization of the OEL display.
FIG. 1 shows a conventional OEL panel. U.S. Pat. No. 5,747,363 discloses a package structure of OEL panel comprising an OEL panel 100 and a substrate 108. The OEL panel 100 is provided with a plurality of stripe anodes 102, an organic light-emitting layer 104 and a plurality of stripe cathode 106. The substrate 108 is provided with a driving chip 112 and a plurality of pins 110. The pins 110 of the substrate 108 are electrically connected to the anode 102 of OEL panel 100 and to the cathode 106 by anisotropic conductive film.
Although the above package structure of OEL panel can effectively integrate the driving chip onto the substrate, there is still a limitation on the size.
FIG. 2 is a schematic view showing the structure of a conventional OEL panel. U.S. Pat. No. 5,693,170 discloses package structure of an OEL panel comprising a plurality of display bricks 200, a common substrate 206 and a plurality of bumps 210. The surface of the common substrate 206 in proximity to the display bricks 200 is provided with a plurality of contact pads 202 which are electrically connected by means of a plug 204 with the electrodes of the display bricks 200. The common substrate 206 is arranged with a plurality of contact pads 208 corresponding to the contact pads 202. The bumps 210 are arranged between the contact pad 202 and the contact pad 208 for electrical connection.
The above package structure of OEL panel can be assembled from a plurality of display bricks to achieve the objective of a large size structure. However, the bonding between the contact pad and the bump is a high re-flow temperature process which will cause warpage to the common substrate, and the high temperature re-flow process will have unfavorable impact on the organic light-emitting layer of the OEL panel.